Burns had state income tax bills of $41,479 in 2015 and $60,335 in 2014. That would mean he had income of at least $500,000 in those years. His tax records for 2016 were not available because he sought an extension.

Screnock had state income tax bills of $6,018 in 2016, $5,295 in 2015 and $6,753 in 2014. Like Dallet, he makes about $131,000 a year as a judge.

Campaign aides to Dallet and Burns declined to say whether they would use their personal wealth to help fund their runs. If they do, any personal donations or loans will be disclosed in campaign filings.

Such funding can prove crucial because Supreme Court campaigns are often shoestring affairs, with much of the spending coming from interest groups that don't have to say where they got their money.

In 2008, Dallet put more than $100,000 of her own money toward her campaign for circuit court judge, campaign finance records show.

Burns used $1,000 of his own money to get his Supreme Court campaign started, which will be shown in a report he files next month, said his campaign manager, Amanda Brink.

She emphasized that Burns would seek donations from ordinary people, saying in a statement that "voters are not looking for a candidate who is simply trying to buy their seat on the bench."

Nathan Conrad, a spokesman for Screnock, said the judge "is not concerned with the bank accounts of his fellow candidates."

"In the coming months, the people of Wisconsin are going to get to know Judge Screnock very well (and) they will see that he doesn't need deep personal pockets to connect with the voters and give them a vision of the judiciary to believe in," Conrad said by email.